Hostname: page-component-586b7cd67f-vdxz6 Total loading time: 0 Render date: 2024-11-28T09:44:32.007Z Has data issue: false hasContentIssue false

Identification of vermiculite by transmission electron microscopy and X-ray diffraction

Published online by Cambridge University Press:  09 July 2018

H. Vali
Affiliation:
Department of Geological Sciences, McGill University, 3450 University Street, Montreal, Quebec, Canada H3A 2A7
R. Hesse
Affiliation:
Department of Geological Sciences, McGill University, 3450 University Street, Montreal, Quebec, Canada H3A 2A7

Abstract

The expandability of K-depleted biotite and natural vermiculite was studied using transmission electron microscopy (TEM) and X-ray diffraction (XRD). K-depletion in layer-silicates was achieved by treating ultrathin sections with 0·1 m CaCl2 and BaCl2 solutions. The natural sample of biotite, which by XRD revealed no expandability on ethylene glycol or glycerol solvation, displayed 10–15% expanded layers when viewed by TEM after alkylammonium intercalation. The proportion of expanded layers increased after CaCl2 treatment. XRD of vermiculite samples revealed two sets of expandable interlayers after alkylammonium treatment, corresponding to two types of particles with different layer structures observed by TEM. Identification of vermiculite by TEM based on basal spacings is reliable with alkylammonium treatment. Intercalation of alkylammonium ions into the interlayers of vermiculite improved the degree of stacking order of the 2:1 layers.

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1992

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Banfield, J.F. & Eggleton, R.A. (1988) Transmission electron microscope study of biotite weathering. Clays Clay Miner., 36, 47–60.CrossRefGoogle Scholar
Calle, C. de la & Suquet, H. (1988) Vermiculite. Pp. 455^96 in: Hydrous Phyllosilicates (Exclusive of Micas)(Bailey, S.W., editor). Reviews in Mineralogy vol. 19, Mineralogical Society of America, Washington, DC.Google Scholar
Ghabru, S.K., Mermut, A.R. & St. Arnaud, R.J. (1989) Layer-charge and cation-exchange characteristics of vermiculite (weathered biotite) isolated from a gray luvisol in northeastern Saskatchewan. Clays Clay Miner., 37, 164–172.Google Scholar
Graf von Reichenbach, H., Wachsmuth, H. & Marcks, C. (1988) Observations at the mica-vermiculite interface with HRTEM. Coll. Polym. Sci., 266, 652–656.Google Scholar
Guthrie, G.D. Jr. & Veblen, D.R. (1990) Interpreting one-dimensional high-resolution transmission electron micrographs of sheet silicates by computer simulation. Am. Miner., 75, 276–288.Google Scholar
Lagaly, G. (1982) Layer charge heterogeneity in vermiculites. Clays Clay Miner., 30, 215–222.CrossRefGoogle Scholar
Lagaly, G. (1987) Clay-organic interactions: problems and recent results. Proc. Int. Clay Conf., Denver,, 343351.Google Scholar
Lagaly, G. & Weiss, A. (1969) Determination of the layer charge in mica-type layer silicates. Proc. Int. Clay Conf. Tokyo, 1, 61–80.Google Scholar
Laird, D. A., Scott, A. D. & Fenton, T.E. (1987) Interpretation of alkylammonium characterization of soil clays. Soil Sci. Soc. Am. J., 51, 16591663.Google Scholar
Marcks, C., Wachsmuth, H. & Graf von Reichenbach, H. (1989) Preparation of vermiculites for HRTEM. Clay Miner., 24, 23–32.CrossRefGoogle Scholar
Olis, A.G., Malla, P.B. «fe Douglas, L.A. (1990) The rapid estimation of the layer charges of 2:1 expanding clays from a single alkylammonium expansion. Clay Miner., 25, 39–50.CrossRefGoogle Scholar
Reynolds, R.C. Jr. (1980) Interstratified clay minerals. Pp. 249-303 in: Crystal Structures of Clay Minerals and their X-ray Identification (Brindley, G.W. & Brown, G., editors). Mineralogical Society, London.Google Scholar
Reynolds, R.C. Jr. (1991) One- and three-dimensional X-ray powder diffraction studied of illite/smectite subjected to different sample preparation methods. Abstracts, 28th Ann. Meet. Clay Minerals Soc., 133.Google Scholar
Ruhlicke, G. & Kohler, E.E. (1981) A simplified procedure for determining layer charge by the n-alkylammonium method. Clay Miner., 16, 305–307.Google Scholar
Slade, P.G., Dean, C., Schulz, P.K. & Self, P.G. (1987) Crystal structure of a vermiculite-anilinium intercalate. Clays Clay Miner., 35, 177–188.CrossRefGoogle Scholar
Spurr, A.R. (1969) A low-viscosity epoxy resin embedding medium for electron microscopy. J. Ultrastructure Res., 26, 3143.CrossRefGoogle Scholar
Stanjek, H. & Friedrich, R. (1986) The determination of layer charge by curve-fitting of Lorentz- and polarization- corrected X-ray diagrams. Clay Miner., 21, 183–190.Google Scholar
Stanjek, H., Niederbudde, E. A. & Hausler, W. (1991) Improved evaluation of layer charge of n-alkylammonium- treated fine soil clays by Lorentz- and polarization-correction and curve fitting. Clay Miner., 27, 3–19.Google Scholar
Vali, H. & Hesse, R. (1990) Alkylammonium ion treatment of clay minerals in ultrathin section: A new method for HRTEM examination of expandable layers. Am. Miner., 75, 14451448.Google Scholar
Vali, H. & Koster, H.M. (1986) Expanding behaviour, structural disorder, regular and random irregular interstratification of 2:1 layer- silicates studied by high-resolution images of transmission electron microscopy. Clay Miner., 21, 827–859.CrossRefGoogle Scholar
Vali, H., Hesse, R. & Kodama, H. (1992) Arrangement of alkylammonium ions in phlogopite and vermiculite: An XRD- and TEM-study. Clays Clay Miner,(submitted).Google Scholar
Vali, H., Hesse, R. & Kohler, E.E. (1991) Combined freeze-etched replicas and HRTEM images as tools to study fundamental-particles and multi-phase nature of 2:1 layer silicates. Am. Miner., 76, 1953–1964.Google Scholar